A double-action mechanical press is capable of easily keeping the dynamic balance, simpler in structure and provides an improved processing accuracy by maintaining the parallelism in upper and lower rams. The double-action mechanical press has a crank mechanism within a double-action crown. The crank mechanism comprises a crankshaft having two of first eccentric sections and two of second eccentric sections. A bed includes two oppositely rotatable toggle linkage mechanisms which rotate oppositely from one another. The two first eccentric sections are connected to the upper ram to move it in the upward and downward directions. The two of second eccentric sections are connected to the lower ram through a plurality of upright rods with the two toggle linkage mechanisms to move the lower ram in the upward and downward directions.